MORPHOLOGICAL CHARACTERIZATION OF BIOERODIBLE POLYMERS .2. CHARACTERIZATION OF POLYANHYDRIDES BY FOURIER-TRANSFORM INFRARED-SPECTROSCOPY

This paper describes the Fourier-transform infrared (FTIR) spectroscop y of a series of polyanhydrides made of the following diacids: sebacic acid (SA); 1,3-bis(p-carboxyphenoxy)propane (CPP); 1,6-bis(p-carboxyp henoxy)hexane (CPH); (carboxyphenoxy)methane (CPM); fumaric acid (FA); 5-(P-carboxyphenoxy)valeric acid (CPV). All the polymers revealed typ ical anhydride peaks corresponding to aliphatic-aliphatic, aliphatic-a romatic, and aromatic-aromatic diads in the wavenumber range 1820-1710 cm-1. Additional paired peaks corresponding to SA-SA diads were ident ified in the fingerprint region at 1382, 1360 and 1307, 1286 cm-1. The second pair was assigned to the crystalline regions of the copolymers . This information allows easy identification of bond distribution in a variety of polyanhydrides, and correlates well with information prev iously presented using nuclear magnetic resonance (NMR) spectroscopy a nd X-ray powder diffraction.