INVESTIGADORES
LEAL DENIS Maria Florencia
artículos
Título:
New copper (II) complexes of polyampholyte and polyelectrolyte polymers: solid-state NMR, FTIR, XRPD and termal analyses
Autor/es:
JUAN MANUEL LÁZARO MARTÍNEZ; ANA KARINA CHATTAH; GUSTAVO ALBERTO MONTI; MARÍA FLORENCIA LEAL DENIS; GRACIELA YOLANDA BULDAIN; VIVIANA CAMPO DALL ORTO
Revista:
POLYMER
Editorial:
Elsevier Ltd.
Referencias:
Lugar: Amsterdam. Netherlands.; Año: 2008 vol. 49 p. 5482 - 5489
ISSN:
0032-3861
Resumen:
Novel solid copper(II) complexes were obtained from the polyampholyte poly(EGDE-MAA-IM) and the polyelectrolyte poly(EGDE-MAA) polymers with copper salts at different concentration levels. The materials were characterized employing solid-state Nuclear Magnetic Resonance (NMR), Fourier Transform infrared (FTIR), X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC) and thermogravimetry (TG). The reticulation induced by MAA in these materials against the poly(EGDE-IM) gel was analyzed by DSC. The coordination behavior of the carboxylic acid of MAA, compared to that provided by the imidazole ring, was studied through solid-state 13C NMR and changes in the FTIR spectra. The non-homogenous character of the doped and undoped materials was analyzed by the glass transition temperature (Tg), 2D 1H-13C WISE NMR and proton spin?lattice relaxation time in the rotating frame (TH1r). In particular, the TH 1r and TH 1 values in the complexes decreased with the Cu(II) concentration, showing the high sensitivity of both parameters to the presence of a paramagnetic ion. Finally, the thermogravimetric studies indicated that the presence of the imidazole ring was decisive for the stability of the Cu(II) complexes and for the undoped polymers.