Infrared Studies on Polymethyl Methacrylate Doped with a Sulphur-Containing Ligand and Its Cobalt (II) Complex During Gamma Radiolysis

ABSTRACT

Infrared spectroscopic studies were performed for poly(methyl methacrylate) samples doped with an organic ligand (N,N-dioxaloyl benzenesulphonyl-N,N-dioxaloylthiocarbazide) and its cobalt (II) complex during gamma radiolysis after extraction of the dopant. There are no drastic changes in the IR-absorption band positions, but noticeable changes in the intensities are found. The relative transmission of IR-absorption bands such as bands at 750, 840, 1065, and 1388 cm⁻¹ were measured relative to the transmission of the carbonyl group band at 1717 cm⁻¹. The degradation and recombination mechanism of different groups in the polymeric chain or backbone during radiolysis are suggested by the behavior of the relative transmission data for each group with increasing exposure dose. The tacticity of the PMMA sample was unchanged during radiolysis and was found to be syndiotactic. This fact is confirmed by measuring the IR J-values for different PMMA samples before and after irradiation. The protection efficiency of the organic ligand and its cobalt (II) complex were also investigated and the organic ligand is a more protective material than the cobalt (II) complex

Keywords:

• PMMA
• gamma radiation
• degradation
• IR-spectroscopy

Notes

The low % of carbon is due to the metal carbide formation. w = water molecules.

D = Degradation process; R = Recombination process.