| dc.description.abstract | Onggok is a by-product from tapioca industry which has solid shape and usually one-fist sized. The main objective of this study was to synthesize superabsorbent polymer (SAP) from onggok dicarboxylic by grafting-crosslinking copolymerization. Onggok oxidation was done in 2 stages, first with NaIO4 and then with 3 variation treatments of H2O2. The oxidation product was copolymerized with acrylic acid monomer by using ammonium peroxydisulfate as initiator and N,N'-methylene-bis-acrylamide as crosslinker at 75 °C for 3 hours. Oxidation with 30% H2O2 produced high carboxyl content, but the absorption capacity of the copolymer product was lower than oxidation with 3% H2O2 producing lower carboxyl content. Neutralization of product with the highest absorption capacity increased the absorption capacity as much as 55%. The maximum absorption capacity in salt solutions was 95.91 g/g observed in 0.01 M NaCl, while in solutions with various pH, it was achieved at pH 7. The structure of SAP was confirmed by Fourier transform infrared spectrophotometry method. | en |
