EROSION OF POLY(ANHYDRIDE-CO-IMIDES) - A PRELIMINARY MECHANISTIC STUDY

A new class of biodegradable polymers that show promising characterist ics for orthopedic applications was investigated. This study examines aspects underlying the polymer erosion of itylimidoglycine-co-1,6-bis( carboxyphenoxy)hexane] and tylimidoalanine-co-1,6-bis(carboxyphenoxy)h exane]. Copolymer degradation was studied by examining the anhydride b ond hydrolysis and copolymer composition by IR and NMR spectroscopy. H ydrolysis of the anhydride bonds occurred much faster than did the dis solution of the hydrolyzed products, leading to the formation of two d istinct erosion zones. The two erosion zones were observed by light an d scanning electron microscopy with erosion originating at the surface and moving to the center of the polymer samples. (C) 1996 John Wiley & Sons, Inc.