A biodegradable aliphatic thermoplastic polyurethane based on L-lysine diisocyanate and 1,4-butanediol hard block segments, and 2000 g/mol poly(epsilon-caprolactone) diol soft block segments was synthesized. The resulting polymer was a tough thermoplastic with ultimate tensile strength of 33 MPa and elongation of 1000%. The polymer displayed classic segmented thermoplastic elastomer morphology with distinct hard block and soft block phases. Thermal and dynamic mechanical analyses determined that the material has a useful service temperature range of around -40 degrees C to +40 degrees C, making it an excellent candidate for low-temperature elastomer and film applications, and potentially as a material for use in temporary orthopedic implant devices. (c) 2006 Wiley Periodicals, Inc.