BAK poly(ester amide)s differing in the amide/ester ratio have been synthesized and characterized, considering spectroscopic data and both thermal and mechanical properties. Degradability under different media (water at 70 degreesC, acid or enzymatic catalysis at 37 degreesC) has also been studied by evaluating the changes in intrinsic viscosity, in the NMR spectra and in the surface texture of samples. The use of chain extenders, such as hexamethylene diisocyanate and 1,3-butadiene diepoxide, has been investigated and the optimal reaction conditions are reported here. Changes on mechanical properties due to the incorporation of biodegradable reinforces have also been evaluated. Finally, the synthesis and determination of thermal properties of related poly(ester amide)s constituted by glutaric or succinic acid instead of adipic acid have been investigated. (C) 2003 Elsevier Ltd. All rights reserved.