The soft segment crystallinity and morphology of poly(ester-urethanes) (PEUs) based on poly(&-caprolactone) (PCL) as a soft
segment and an aliphatic diisocyanate in the hard segment were studied. It was found that the restriction of the crystallization
of the PCL soft segment depends on the hard segment concentration, the length of the soft segment, and the total molecular
mass of the PEUs. The PEU based on a low molecular mass PCL (M=2000) is an amorphous elastic material during a long time after
casting from solution or after melt crystallization. A soft-hard segment endothermal mixing transition (Tmix) of about 70-80C is observed in the DSC curves of this PEU sample.