Differential scanning calorimetry and thermally stimulated current spe
ctroscopy have been applied to the characterization of the microstruct
ure of polyurethane/polyurethane bilayers. The microstructure of the c
onstituting polyurethane monolayers was used as reference. It is const
ituted of two phases indicating the segregation of soft and hard seque
nces. In bilayers, the microstructure is strongly dependent upon the r
ecovering time. The microstructure is also modified upon ageing.