The morphology of the segmented polyurethanes synthesized using various chain extenders studied by AFM method

The morphological structure of the segmented polyetherurethanes (PU) has been studied using atomic force microscopy. The polymers were synthesized from poly(oxytetramethylene)diol (PTMO), 2,4-TDI and various low molecular weight diols or diamines as chain extenders. The length of the PTMO based soft segments, predeterminated by the molecular weight of the macrodiol (Mn=1000), and the length of the hard segments resulted from the initial molar ratio of the reagents (PTMO/TDI/ChEt 1:4:3), were kept unvaried for this set of polyurethanes. Hence, the observed variations in the morphology of the investigated polyurethanes can be directly attributed to the molecular structure of the hard segments resulting from the chain extender used.