| dc.description.abstract | Carbohydrates of onggok consist mostly of starch and cellulose fractions. Both fractions have high potential for modification to a superabsorbent. Onggok with Ammonium persulfate serves as an initiator, acrylamide serves as a monomer, and N,N-methylenebisacrylamide as a cross-linker. Onggok was activated using 60% H2SO4 at 60 oC for 1 hour and saponified using with 1M NaOH at 90 oC for 2 hours. The best ratio of onggok:water was 1:30, and the optimum temperature was 70 oC for obtaining the highest water absorption capacity. Absorption capacity was of the non-starch fraction, non-starch fraction plus activation, non-starch fraction plus saponification, and non-starch fraction plus activation plus saponification treatments were 25.21, 53.37, 273.3 and 262.07 g/g, respectively. The effect of activation treatment was not significant, while that of saponification increased significantly its absorption capacity. Scanning electron microscopy micrograph of non-starch fraction showed that starch granules were disappeared by HCl hydrolysis treatment. It indicated that the process hydrolysis succeeded. Fourier transform infrared spectroscopy spectrum showed a new peak at wave number of 1600 cm-1 that indicated an amide group, meaning that the grafting cross-linking process was succeeded and at 3300 cm-1 showed a sharp absorption peak that indicated the activation treatment was succeeded as well. | en |
