摘要 |
An improvement in known processes for preparing substituted carboxylic acids useful as acylating agents which comprise reacting (A) at least one aliphatic polymer of one or more lower olefins with (B) an acid reactant selected from the group consisting of fumaric acid, itaconic acid, maleic acid, and the corresponding anhydrides, lower alkyl esters, acyl chlorides and acyl bromides, in the presence of chlorine can be improved by the steps of (i) reacting at a temperature of about 100<o>-200<o>C, a mixture of (A) and (B) in the presence of about 0.05 to 0.15 equivalent of chlorine per equivalent of (A) until of the chlorine has reacted to provide a first intermediate product, (ii) continuing the reaction in the absence of chlorine at a temperature of from about 180<o>-250<o>C until a conversion of 0.4 to 1.1 equivalents of (B) per equivalent of (A) is attained to provide a second intermediate product, and (iii) reacting said second intermediate with about 0.2 to 1.5 equivalents of chlorine per equivalent of (A) used in step (i) at a temperature of about 180<o>-225<o>C. The carboxylic acids produced by this improved process can be used, per se, in lubricants and fuels and as acylating agents in reactions with amines, alcohols, reactive metals or reactive metal compounds to form derivative products which are useful, for example, as additives for lubricants and normally liquid fuels. |