SYNTHESIS AND CHARACTERIZATION OF DEGRADABLE POLY(ANHYDRIDE-CO-IMIDES)

A series of poly(anhydride-co-imides) based on trimellitylimidoglycine (TMA-gly), pyromellitylimidoalanine (PMA-ala), sebacic acid (SE), or 1,6-bis(carboxyphenoxy)hexane (CPH) were synthesized by condensation polymerization. Monomers and polymers were characterized by NMR and IR spectroscopy, elemental and thermogravimetric analyses, and thermal transition temperatures. Contact angle, intrinsic viscosity, and compressive strength measurements were also performed on the polymers. For all polymer systems, the molecular weights decreased as the amount of imide in the backbone increased. Polymers containing CPH are more hydrophobic, have higher compressive strengths, have higher glass transition and decomposition temperatures relative to polymers containing SA, and exhibit no melting transitions. The mechanical and thermal stability of the materials are increased by the incorporation of imide groups in the polymer backbone. The selection of imide monomers, TMA-gly vs PMA-ala, can significantly affect the resulting polymer characteristics. Both imide monomers affect the hydrophobicity of the resulting polymers in similar ways, with the materials becoming more hydrophilic as the imide content is increased. However, polymers containing PMA-ala have thermal transition temperatures that are higher than the corresponding polymers with TMA-gly.