Characterization of Local Structures in Flexible Polyurethane Foams by Solid-state NMR and FT-IR spectroscopy

摘要

The paper examines the characterization of local structures in water-blown flexible polyurethane foams with various amine catalysts. In this study, we have applied solid-state NMR relaxation, nuclear spin diffusion and FT-IR microscope analysis on flexible polyurethane foams. Quantitative knowledge of the polymer structure and dynamics by these methods provided significant insight on understanding microphase separation and the domain structure of urethane and urea hard segments and polyether soft segments in foam. Furthermore, we analyzed the influence of hydrothermal degradation on the microphase structure of the foams. A detailed comparison of the fundamental results with conventional foam durability tests (e.g. humid aged compression sets) is described, and the hydrothermal degradation mechanism and the influence of catalysts on the foam stability are discussed.