New polymer syntheses. Part 7. New unsaturated polyurethanes: synthesis and characterization †

A novel series of polyurethanes was prepared via step‐growth solution polymerization, by reaction of arylidene monomers, e g 2,5 bis(4‐hydroxybenzylidene)cyclopentanone ( I ), 2,5‐divanillylidenecyclopentanone ( II ), 2,6‐bis(4‐hydroxybenzylidene)cyclohexanone ( III ), 2,6‐divanillylidenecyclohexanone ( IV ) or 2,7‐bis(4‐hydroxybenzylidene)cycloheptanone ( V ) with diisocyanates such as toluylene diisocyanate and methylene bis(4‐phenylisocyanate). To characterize these polymers, the corresponding model compounds were prepared from monomers I–V and phenylisocyanate. The polymers were characterized by reduced viscosity measurements, IR spectroscopy, 1 H NMR, solubility and determination of their crystallinity. Characterization of the model compounds was accomplished by elemental analysis, IR and 1 H NMR spectroscopy. The thermal stabilities of the polymers were evaluated by thermogravimetric analysis. The morphology of one of these polymers was examined by scanning electron microscopy. © 1999 Society of Chemical Industry