Química Nova (Jan 2012)

Application of ftir in the determination of acrylate content in poly(sodium acrylate-co-acrylamide) superabsorbent hydrogels

  • Antônio Sávio G. Magalhães,
  • Manuel P. Almeida Neto,
  • Maslândia N. Bezerra,
  • Nágila M. P. S. Ricardo,
  • Judith P. A. Feitosa

DOI
https://doi.org/10.1590/S0100-40422012000700030
Journal volume & issue
Vol. 35, no. 7
pp. 1464 – 1467

Abstract

Read online

Hydrogels have been prepared by free-radical solution copolymerization of acrylamide and sodium acrylate (NaAc), with molar ratio ranging from 25/75 to 80/20, respectively, using methylene bisacrylamide as the crosslinking agent. A FTIR spectroscopy procedure to determine the acrylate/acrylamide ratio in these hydrogels was proposed based on absorbance at 1410 cm-1 (nCOO-) and 2940 cm-1 (nCH and nCH2). A straight line with a good linear correlation coefficient (0.998) was obtained by plotting the acrylate content (Ac%) versus relative absorbance (Arel = A1410/A2940). Results were confirmed by the amount of sodium cation released in acid medium determined by atomic absorption spectrometry.

Keywords