Sintesa Superabsorben dari Natrium Alginat dengan Metode Grafting-Crosslinking dengan dan Tanpa Komposit

Abstract

Indonesia is the second largest algae producer in the world. Nevertheless, the algae is just dried and exported or extracted to become carrageenan, sodium alginate, or agar. According to its chemical composition, the algae has a potency to be developed such as biodiesel, pharmaceutical products, etc. The goal of this research is to develop superabsorbent based on sodium alginate. Superabsorbent is a hydrophilic material which can absorb and retain large amount of water. Commercial superabsorbent is mostly synthesized from chemical substances which are less eco-friendly. The synthesis of superabsorbent was done by reacting 5% sodium alginate solution with acrylic acid and/or acrylamide at the certain ratio: 1:0; 1:3; 1:1; 3:1; and 0:1, using ammonium persulfate as initiator. To crosslink and strengthen the macromolecules was used N.N’-methylenebisacrylamide as crosslinker, and bentonite as composite. Water absorbency capacity was measured in pH 3, 7, and 11 solution.The highest water absorbency was obtained at 5%-w/w        sodium alginate; 0,02 mol/L initiator; 1:1 ratio of acrylic acid and acrylamide; 0,007 mol/L crosslinker, and without composite in pH 7 solution.