Biodegradable poly(ethylene oxide)/poly(epsilon-caprolactone) multiblock copolymers.

A series of poly(ethylene oxide) (PEO)/poly(ϵ-caprolactone) (PCL) containing biodegradable poly(ether ester urethane)s, covering a wide range of compositions, were synthesized and characterized. The synthesis consisted of a two-step process. During the first step, the ring-opening reaction of ϵ-caprolactone was carried out, initiated by the hydroxyl terminal groups of the PEO chain. The second step involved the chain extension of these PCL–PEO–PCL tri- mers with hexamethylene diisocyanate. By varying either the ethylene oxide/ϵ-caprolactone ratio or the length of both segments, we obtained a series of polymers having different morphologies and displaying a broad range of properties. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 273–281, 2002