A composition comprising a hydrocarbon polymer having attached thereto pendant groups A.sub.a and B.sub.b wherein each A is independently selected from members of the group consisting of: groups of the formula ##STR1## and each B is independently selected from members of the group of formula: ##STR2## wherein each X is independently O, S, or NR.sup.b, and each Z is independently a group of the formula ##STR3## R.sup.a is an ethylene group, a propylene group, which groups optionally have hydrocarbyl or hydroxyhydrocarbyl substituents, or ##STR4## wherein J is H, SH, NH.sub.2, or OH, and tautomers thereof; a is 0 or a number ranging from 1 to about 50, and b is a number ranging from 1 to about 30; wherein each of the groups is defined in greater detail herein.