Synthesis and characterization of calcium-containing poly(urethane-urea)s

A calcium salt of mono(hydroxyethoxyethyl)phthalate [Ca(HEEP)2] was synthesized by the reaction of diethylene glycol, phthalic anhydride, and calcium acetate. Four different bisureas like hexamethylene bis(omega,N-hydroxyethylurea), tolylene 2,4-bis(omega,N-hydroxyethylurea), hexamethylene bis(omega,N-hydroxypropylurea), and tolylene 2,4-bis(omega,N-hydroxypropylurea) were prepared by reacting ethanolamine or propanolamine with hexamethylene diisocyanate (HMDI) or tolylene 2,4-diisocyanate (TDI). Calcium-containing poly(urethane-urea)s (PUUs) were synthesized by reacting HMDI or TDI with 1:1 mixtures of Ca(HEEP)2 and each of the bisureas using di-n-butyltin dilaurate as a catalyst. The PUUs were well characterized by Fourier transform infrared, 1H- and 13C-NMR (nuclear magnetic resonance), solid-state 13C cross-polarization-magic angle spinning NMR, viscosity, solubility, elemental, and X-ray diffraction studies. Thermal properties of the polymers were also studied by using thermogravimetric analysis and differential scanning calorimetry. (C) 2003 Wiley Periodicals, Inc.