Applications of SR-XRF to characterize biogels obtained by irradiation of dilute aqueous biopolymers solutions

R.D. PEREZ; M. RUBIO; C.A. PEREZ; S.F. AUSAR; D. BELTRAMO; A. GERMANIER; I.D. BIANCO

RADIATION PHYSICS AND CHEMISTRY (OXFORD)

Elsevier

Lugar: OXFORD; Año: 2004 vol. 71 p. 999 - 999

0969-806X

uring the iiradiation of aqueous solutions of polymers with X-rays, chemical reactions are produced by means of reactive species such as hydrated electrons, hydroxyl radicals and hydrogen atoms. Intermolecular crosslinking reactions result in linking polymer chains, thus they lead to the formation of macroscopic hydrogels. Two additional advantages are obtained when radiation is used to form hydrogels: sterilization and "permanent" covalent crosslinked networks. The goals of this study are: 1) A new methodology to determine the diffusion coefficient of low atomic weight molecules in radiation-formed hydrogels. In so-doing, a high degree of collimation of the synchrotron beam is used, 2) Direct measurement by grazing exit (GE) XRF of the polymer concentration profile near the air-gel interface, being otherwise generally not easily accessible by experiments. It is known that due to the strong interaction of polymer molecules in aqueous solutions, an enhanced concentrations layer (of thi