Polyester lubricant additives, their preparation and compositions containing them

A polyester suitable for use as a lubricant additive which is the product of the reaction at elevated temperature from reflux up to about 210.degree. C. with removal of water of a polyolefin substituted succinic acid or anhydride wherein said polyolefin substituent has a molecular weight of about 700-3,000 with a substituted carboxypyrrolidone of the following formula A ##STR14## in which a. R is selected from the group consisting of a hydrogen atom, an alkyl containing up to 8 carbon atoms, a phenyl group, a benzyl group, a hydroxyalkyl group containing 1-3 hydroxy radicals, a polyoxyalkylenealkyl group containing up to an average of about 2 oxyalkylene groups, a hydroxyalkylaminoalkyl group, a carboxypyrrolidone substituted C.sub.2-6 alkyl group, and an imidazoline substituted C.sub.1-4 alkyl group,

• b. each R.sup.1 is independently selected from a group consisting of ##STR15## c. R.sup.2 is alkylene containing 2-6 carbon atoms d. R.sup.6 is selected from the group consisting of alkyl groups containing up to 8 carbon atoms, polyoxylalkyene alkyl groups containing up to an average of about 2 oxyalkylene groups, hydroxyalkyl groups containing 1-3 hydroxy radicals, imidazoline substituted C.sub.1-4 alkyl groups, and groups having the formula ##STR16## in which the groups R and R.sup.2 independently are as herein defined, e. R.sup.7 is selected from the group consisting of alkyl groups containing up to 8 carbon atoms, hydroxyalkyl groups containing 1-3 hydroxy radicals, dialkylaminoalkyl groups, hydroxyalkylaminoalkyl groups, imidazoline substituted C.sub.1-4 alkyl groups, groups having the formula ##STR17## and groups having the formula ##STR18## in which the groups R and R.sup.2 independently are as herein defined, f. R.sup.8 is selected from the group consisting of hydrogen, alkyl groups containing up to 8 carbon atoms, hydroxyalkyl groups containing up to 3 hydroxy groups, dialkyl aminoalkyl groups, imidazoline substituted C.sub.1-4 alkyl groups, hydroxyalkylaminoalkyl groups and groups having the formula ##STR19## in which the groups R and R.sup.2 independently are as herein defined, and g. provided that there are a total of from 2-6 free hydroxy groups on groups R and/or R.sup.1.