As used herein, the term oxa ester may include: [0127] (a) monoesters of the formula: [0128] b) diesters of formula: [0129] wherein n is an integer greater than or equal to 1, preferably from 1 to 27, R1 and R3 are typically CH3, but may be any organic moiety selected from the group consisting of a linear or branch chained alkyl, a substituted or unsubstituted carbocyclic or heterocyclic groups, a