Synthesis and characterization of interpenetrating polymer network based on sodium alginate and methacrylic acid and potential application for immobilization of Ti[O.sub.2] nanoparticles

An interpenetrating polymer network (IPN) based on the sodium alginate (A) and partially neutralized poly(methacrylic acid) (MAA) was prepared by free radical polymerization followed by additional cross-linking of sodium alginate with calcium ions. Obtained material (A/MAA IPN) was characterized by FTIR spectroscopy, thermogravimetric analysis, scanning electron microscopy, and rheological measurements. Swelling behavior of synthetized IPN has been also investigated. Ti[O.sub.2] nanoparticles (Ti[O.sub.2] NPs) were immobilized onto A/MAA IPN by dip-coating method and obtained Ti[O.sub.2]/IPN nanocomposite was used for removal of the methylene blue (MB) from aqueous solution. The photodegradation (under illumination) and sorption (in the dark) processes for dye removal were monitored through decrease of dye concentration in the solution by UV/VIS spectrometer. The Ti[O.sub.2]/IPN nanocomposite sorbed approximately 93% of the MB from a 10 mg [L.sup.-1] MB solution in the dark, but no degradation occurred. Likewise, more than 93% of dye was removed after 8 h of illumination. However, after 24 h of illumination, the samples were discolored indicating that dye molecules were successfully degraded. Thus, the Ti[O.sub.2]/IPN nanocomposite could be utilized in the photodegradation-sorption process for the abatement of pollutants in water.
INTRODUCTION Hydrogels are a water-swollen, and cross-linked polymeric networks produced by simple reaction of one or more monomers [1, 2]. Interpenetrating network type hydrogel (IPN) is formed by interpenetration of [...]