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Poly(ester-N-substituted urethane)s with carboxylate groups. Synthesis, characterization and solution properties

Domenii publicaţii > Chimie + Tipuri publicaţii > Articol în revistã ştiinţificã

Autori: E. C. Buruiana, M. Olaru, T. Buruiana, B. C. Simionescu

Editorial: Rev. Roum. Chem., 49, p.753-759 , 2004.

Rezumat:

A convenient alternative to incorporate carboxylate units on urethane nitrogen atoms through polymer modification of a neutral polyesterurethane with a cyclic monomer, i.e., maleic anhydride, is proposed. The method yields new polyurethane anionomers. Under optimum reaction conditions, polyanions with a degree of substitution corresponding to an ionic content of 30 and 80 meq ionic groups/100 g polymer, respectively, were obtained. These carboxylate anionomers were structurally characterized with respect to a low molecular model and the parent precursor. The results of a viscometric study of anionomers in extremely dilute solutions indicated a polyelectrolyte behavior from 25 to 60 C degrees, while at higher concentrations the aggregation of ion pairs was noted.

Cuvinte cheie: polyurethane anionomers