SYNTHESIS OF N-SUBSTITUTED DIISOPROPANOLAMINES, THEIR SEBACATE POLYESTERS AND POLYURETHANE ELASTOMERS

Abstract

Several N-substituted diisopropanolamines were prepared by reacting aqueous solutions of amines with excess propylene oxide at ordinary pressure but higher N-substituted diisopropanolamines had to be prepared in an autoclave at 200 °C. The ionization constants of these bases were measured and recorded as pKa values. Their infrared absorption spectra gave bands common to all diisopropanolamines mainly at 3.04, 7.14, 7.55, 7.85, 9.45, 10.6, and 11.95 microns. Their condensation with sebacic acid gave the corresponding polyesters, which were soluble in strong acids and had molecular weights of about 1500. The hydroxyl-terminated polyesters were cured with a slight excess of 2,4-tolylene diisocyanate at 100 °C for 2 days to yield elastomers of brittle temperatures in the region of −50 °C.