EFFECT OF LAPONITE RD ON THE DYE ADSRPTION OF CARALG NANOCOMPOSITE HYDROGELS

CarAlg/Lap nanocomposite hydrogels were synthesized from grafting of AAm onto binary mixture of Car and Alg biopolymers by incorporationof Laponite RD as inorganic crosslinker andnanofiller. In brief, Laponite RD clay (0, 0.1, 0.25, 0.5, and 0.75 g) was poured into 50 mL of distilledwater and stirred for 5 h. Then, 0.5 g of Car and 0.5 gof Alg were added to solution and the temperature of solution was adjusted at 70 oC. After completedissolution of biopolymers, the dissolved oxygen was removed by bubbling of N2 gas for 30 min. 0.1 g of APS initiator (dissolved in 2 mL water) was added tothe solution and finally 3 g of AAm monomer was poured into solution. The produced hydrogels were kept in an oven at 70 oC for 48 h. Then,nanocomposites were dried at 50 oC for constant weight. The dried hydrogels were grinded and passed from 40-mesh size sieve to obtain uniform samples.The hydrogels were kept away from moisture and light. The samples were shown as CarAlg/Lapz that the suffix z indicates the wt% of laponite in initialfeed composition. The nanocomposites containing only Car or Alg biopolymer were synthesized as above by dissolving1 g of Car or Alg. The samples were shown with Car/Lap5 and Alg/Lap5 labels that 5 suffix show the weight percentage of laponite in polymerization feed