Thermal Analysis of Polyurethane Block Polymers

Abstract

An analysis of data from differential scanning calorimetry and infrared spectroscopy for a series of polyurethane block polymers is presented. It is found that the DSC endotherms observed result from short- and long-range ordering of the hard segments, rather than from hydrogen-bond dissociation as previously thought. Hydrogen-bond disruption as studied by infrared spectroscopy is influenced primarily by the glass transition temperature of the hard segments. Differences in domain morphology of these materials, which are sensitive to sample thermal history, are not revealed by changes in the extent or thermal stability of the hydrogen bonds. An explanation for the lack of correlation between hydrogen-bond effects and the DSC endotherms is presented. © 1973, American Chemical Society. All rights reserved.