Polyoxymethylene (POM) is an important plastic with pretty good properties. However, its poor impact strength and thermo-degradation limit its applications. In this paper, the polycaprolactone based thermoplastic polyurethane (TPU-1) with a Shore A hardness of 80 was selected to toughen POM，because this kind of TPU has the excellent mechanical properties and matchable viscosity with POM at the processing temperature around 190 ℃. The result shows that TPU-1 can effectively enhance the notched impact strength of POM and when the content of TPU increases to 40%, the notched impact strength of POM/TPU-1 blend abruptly increases and the co-continues phase structure forms. The elongation at break increases, while the tensile strength and modulus decrease with the increase of TPU-1 content. TPU-1 can extract some of the additives in POM, affect the crystallization process, and increase the thermo-degradation temperature of POM.
