SYNTHESIS AND CHARACTERIZATION OF HYDROGEL FORMED BETWEEN SODIUM ALGINATE AND ACRYLAMIDE AND STABILIZED BY Ca+2 IONS

Abstract

A hydrogel made up by 86% in mass of water and 14% in mass of alginate and acrylamide at proportion of 1: 6 was synthezied with the use of the crosslinking agent N,N-methylene-bys-acrylamide, the thermo-initiator ammonium persulphate and polymerization accelerator N,N,N’,N’-tetramethylethlenediamine at the molar fractions of 0,028; 0,031 and 0,152 mol%, respectivety, corresponding to the acrylamine monomer. After the mixture of the reagents, the hydrogel was taken to a furnace in order to cure and, after the cure step, it was submerged in a 0,3 mol/L solution of calcium carbonate in order to exchange the sodium ions present on the alginate for the calcium ions in solution. The resulting hydrogel was submitted to chemical, mechanical and thermal caracterizations, which were composed by tests of density,compression and thermogravimetric analysis. It was verified that the hydrogel synthezied on this research achieved greater mechanical resistance and lower elasticity in comparison to another works. From the chemical and thermal characteristics results, it was shown that the hydrogel was caracterized by bonding and reaction characteristics of a hibryd hydrogel of acrylamide and alginate.