Biologically absorbable coatings for implantable devices based on polyesters and methods for fabricating the same

A polymer comprising a structure of a formula:

• where R1 and R3 are different from each other and each comprises a component independently selected from a group consisting of a chemical bond, substituted, unsubstituted, hetero-, straight-chained, branched, cyclic, saturated and unsaturated aliphatic radicals;
• and substituted, unsubstituted, and hetero-aromatic radicals;
• R2 and R4 each comprises a component independently selected from a group consisting of substituted, unsubstituted, hetero-, straight-chained, branched, cyclic, saturated and unsaturated aliphatic radicals;
• and substituted, unsubstituted, and hetero-aromatic radicals;
• the grouping
• is derived from polyacid HOOC—R1—COOH and diol HO—R2—OH;
• the grouping
• is derived from polyacid HOOC—R3—COOH and diol HO—R4—OH;
• R1 and R3 are selected so that polyacid HOOC—R1—COOH and polyacid HOOC—R3—COOH independently have two more carboxylic acid groups;
• polyacid HOOC—R1—COOH or polyacid HOOC—R3—COOH is an aliphatic dicarboxylic acid selected from the group consisting of oxalic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecandioic acid, tridecanedioic acid, tetradecanedioic acid, petadecanedioic acid, hexadecanedioic acid, citric acid, maleic acid, fumaric acid or combinations thereof;
• L1 is an optional linkage;
• X is an optional agent;
• L2 is an optional linkage connecting X to the polymer;
• and
• m and n are integers not equal to 0.