Preparation and Properties of Poly(urethane-imide)s Derived from Diisocyanates Containing Build-in Imide Rings

ABSTRACT, Poly(urethane-imide)s were prepared by polycondensation reaction of four imides containing diisocyanates with poly(tetramethylene oxide)glycol. Synthetic procedures for the preparation of the diisocyanates were described. The chemical structures of the monomers and polymers obtained were character-ized by IR, ' H NMR, and mass spectroscopies. The physical properties of polymers including solution viscosity, solubility properties, thermal stability and thermal behaviour were studied as well. The polymers showed excellent solubility in polar aprotic solvents such as DMF, DMAc and NMP. Their inherent viscosities were in the range of 0.50–0.55 dig. Tio % obtained as a criterion of thermal stability was in the range of 316–335 'C for the polymers. Key Words: poly(urethane-imide), polyurethane, diisocyanate, curtius rearrangement, thermal stabilit