Synthesis and characterization of polycaprolactone-based segmented polyurethanes

Abstract

Segmented polyurethanes were synthesized by the reactions of poly(ε-caprolactone) (PCL)-diol and 1,6-hexamethylene diisocyanate through bulk polymerization without using solvent, initiator, or catalyst. Phase separationand hydrogen bond formation between hard segments or between hard and soft segments were examined by Fouriertransform infrared spectroscopy (FTIR)-ATR and X-ray diffraction (XRD), while physical and mechanical propertieswere studied by atomic force microscope, differential scanning calorimeter, dynamic mechanical analysis, and tensiletester. When the diisocyanate content was increased, deconvolution results of FTIR-ATR in C=O and N-H regionsdemonstrated better miscibility of the segments and XRD results showed a significant decrease in the crystallinity of softsegments. Samples having strong hard segment interactions displayed better mechanical properties.