Polymers currently used for orthopedic applications do not have the mechanical strength to be used in high load bearing fractures. In addition, upon degradation a large concentration of acid is released into the surrounding tissues. A new class of polymers is proposed to address these limitations. Through the incorporation of either L- phenylalanine, L-tryptophan, or L-tyrosine into poly(anhydride-co- imide) polymers, increased mechanical strength, slow degradation, and nontoxic degradation products may be achieved. These amino acids were chosen because of their large, bulky side chains. In addition, phenylalanine is very hydrophobic, which may add additional stability to its copolymers. To synthesize these polymers, either trimellitic or pyromellitic acid derivatives will be fused with the individual amino acids mentioned above to form the imide diacids. Each monomer will be activated, then polymerized with the prepolymer of 1,6-(p- carboxyphenoxy hexane). The resulting copolymers will be fully characterized and evaluated for mechanical strength, biocompatibility, and biodegradability. If successful, these polymers will be useful for orthopedic implants in all situations, including fractures involving high weight-bearing areas.
