Synthesis and Characterization of Sodium Alginate Based Gel Films Sodium alginate (SA) is a biocompatible polymer with natural origin and it is both pH- and electro-responsive polymer. In this study, four types of SA films were prepared: linear chained SA films (SA/SA2) that were prepared by evaporating/drying the solution of SA in water, SA-AA semi-IPN gel films that were prepared with different initial concentrations of acrylic acid (AA), cross-linked SA films (SA-Ca-40/SA2-Ca-40) that were prepared by cross-linking of SA with Ca2+ ion and SA-AA-GA IPN films that were prepared by cross-linking of SA in SA-AA semi-IPN films with glutaraldehyde (GA).
The characterization of these films was performed by FTIR, XRD and DSC analyses. The dielectric properties (dielectric constant ', dielectric loss '' and complex electrical modulus M*) at 12 Hz - 100 kHz frequency range at room temperature and swelling behavior of the films in distilled water were also determined. The effects of the presence and the increase in the content of homopolymer of AA (PAA) in SA-AA semi-IPN films and the cross-linking of SA with Ca2+ ion on the swelling behavior and dielectric properties of the films were investigated.
' and '' values of SA-AA/SA2-AA semi-IPN films decreased with the increase in frequency. In SA-AA and SA2-AA semi-IPN films, the relaxation time increased with the increase in the content of poly(acrylic acid) (PAA). The partially crosslinking of SA with Ca2+ ion did not considerably affect the thermal properties.
