| 摘要 |
A process for preparing a polyalkenyl succinic acid or anhydride comprises heating a mixture of a polyalkene with an unsaturated acidic reagent to a thermal ene reaction temperature until at least 50 wt.% of the polyalkene has reacted, followed by exposure to a halogen gas in the presence of an additional amount of the acidic reagent. The polyalkene is typically a highly reactive polyisobutene (HR-PIB) having a number average molecular weight of 800-5000. The acid reagent may be maleic acid, a maleic anhydride, a maleate, a maleimide, maleonitrile, maleanic acid, fumaronilic acid, fumaric acid, a fumarate, or fumaronitrile. The heating step may comprise the addition of aluminium chloride, boron trifluoride or iron (III) chloride Lewis acids. A further step is also disclosed in which the polyalkenyl succinic acid or anhydride is subsequently reacted with a polyamine to form a hydrocarbyl succinimide, which is a useful dispersant lubricant additive. |
