Roles of phase separation and crystallization in the structure formation of new segmented polyurethane ureas and their nanocomposites with single-walled carbon nanotubes

Crystal structure and supramolecular organization of new segmented thermoplastic polyurethane ureas and their nanocomposites with ultra-small additives (less than 0.1 wt.%) of single-walled carbon nanotubes (SWCNTs) have been been investigated using DSC and X-ray diffraction analysis. Taking into account the Avrami model, effects of physical aging and thermal history of the samples on the crystallization rate was described. It was demonstrated that the introduction of ultra small amounts of SWCNTs does not decrease the crystallinity, but decreases the crystallization rate.