Chromophoric polyureas with pendant 3-hydroxynaphthalene group: synthesis and characterization

The reaction of 4-(3-hydroxynaphthalene)-1,2,4-triazolidine-3,5-dione (3HNTD) with n-propylisocyanate was performed at different molar ratios. The resulting monosubstituted urea and disubstituted urea-urethane derivatives were obtained in high yields and were used as model compounds for polymerization reactions. 3HNTD as a monomer was used in the preparation of heterocyclic poly(urea-urethane)s to produce photoactive polymers, by polycondensation with different diisocyanates in N,N-dimethylacetamide (DMAc) solution. Chromophoric heterocyclic polymers containing naphthalene group, obtained in quantitative yields, possessed inherent viscosities in the range of 0.14–0.38 dL/g. The resulting poly(urea-urethane)s is insoluble in most organic solvents, but easily soluble in polar solvents such as dimethyl sulfoxide (DMSO), DMAc, and N-methylpyrrolidone (NMP). The polymers were characterized by IR, ¹H-NMR, elemental analysis, and TGA. Fluorimetric and UV–vis studies of the monomer as well as polymers were performed.