Acrylic acid is a hydrophilic monomer which becomes the most popular material used to synthesize superabsorbent polymer. In this recent study, acrylic acid was partially neutralized with KOH and mixed with chitosan to form a superabsorbent hydrogel poly (acrylic acid)-graft-chitosan by using of gamma ray irradiation technique. The aim of this study was to determine the optimum composition of KOH in acrylic acid partial neutralization process for enhancing the production of grafted polymer. The degree of neutralization was varied (0, 25, 50, 75, and 100)% and the effect on the superabsorbent characteristics were studied. Hydrogel products were characterized by Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM). The gel content, swelling ratio, Equilibrium Degree of Swelling (EDS), and Thermal Analysis were also performed. The highest water swelling capacity was 715 (g water/g dry hydrogel), and the gel content was 91.23%, resulted from 75% of acrylic acid neutralization. The swelling capacity of the products was also tested in urea and NaCl solutions and reached 750 (g urea solution/g dry hydrogel) for urea and 378,33 (g NaCl solution/g dry hydrogel) for NaCl. The huge water absorption capacity indicated that the hydrogel from this research was a superabsorbent product which was suitable for hygiene products application. The degree of neutralization did not show a significant influence on the thermal resistance of the grafted hydrogel produced in this study.

No abstract

The composition of mineral and vitamin from breadfruit is particularly known of having benefits compared to rice which is a main source of carbohydrate consumed by societies. The process of drying is one of the factors that affects foodstuffs quality. The aim of this research was to provide an understanding of drying phenomena from data experiment and discover the influence of drying air temperature to breadfruit drying time and rates. This research was conducted in several stages which are material preparation (breadfruit) by through downsizing process, then weigh the material (breadfruit) once every 5 minutes on each drying air temperature variations (50 ºC, 60 o C, 70 o C, and 80 o C). The research were conducted using breadfruit with the best drying time which is obtained at 60 0 C for 100 minutes. The lowest water content obtained was 0.4%, while the highest drying rate was 0.00144 Kg 2 /m 2 .s at 80 ºC of temperature.

No abstract

No abstract