PREPARATION AND CHARACTERIZATION MAGNETIC HYDROGEL

Abstract

Every year more than 100,000 kinds of commercially available dyestuff are produced. Most of industrial dyes have synthetic origin, which are applied in many industries such as textiles, rubber, paper, plastics, leather, petrochemicals etc. The textile industry is one of the major consumers of dyestuff and the effluent from textile industries carries a large number of dyes and other additives which are added as auxiliary chemicals. During the dyeing process some of dyestuff does not bind and approximately 10-15 % of them remains in the wastewater effluents. The release of synthetic dyes to the environment cause serious environmental problems and detrimental effects to human health. Therefore development of an effective treatment method for removing dyes from wastewater is of great significance. In this study poly(vinyl) alcohol hydrogels containing different amounts of magnetic particles were prepared and characterized for dye adsorption from wastewater. The magnetic particles synthesized by co-precipitation methos were dispersed in aqueous poly(vinyl) alcohol solutions. The solutions were then physically crosslinked by the freezing-thawing method. The hydrogels prepared were characterized for their drying, swelling and gelation properties. It was found that the hydrogels has high water absorption capacity (equilibrium degree of swelling: 200–214% and equilibrium water content: 66–68%) and high crosslinking degree (95%) almost independent from their magnetic particle content. They gained magnetic property after addition of the magnetic particles in the polymer matrix.

Keywords

• poly(vinyl) alcohol
• swelling behaviour
• freeze-thaw
• magnetic hydrogel