ANALYSIS OF POLYURETHANES USING CORE EXCITATION SPECTROSCOPY .1. MODEL POLYURETHANE FOAM POLYMERS

The C1s, N1s, and O1s excitation spectra of model methylenediphenyldii socyanate (MDI) polyurethanes with well known structures have been rec orded using electron energy loss spectroscopy (EELS) in an electron mi croscope. These spectra are compared to the core excitation spectra of selected small molecule analogue species (recorded by gas phase EELS) in order to identify transitions characteristic of various structural components found in polyurethanes. A more detailed report on the smal l molecule analogue spectra is presented in the following article. Spe ctral features characteristic of the different structural components i n polyurethanes are identified in the spectra of the model polymers. T hese can be used as the basis for chemical studies of micron or submic ron sized segregated phases in flexible polyurethane polymers. (C) 199 5 John Wiley & Sons, Inc.