Synthesis of Sustainable Superabsorbent Biopolymer: Modified Rice Straw Cellulose with Initiator and Crosslink Agent

Abstract Superabsorbent biopolymers are polymer-based materials that have high absorption capabilities made from synthetic monomers modified with natural monomers such as cellulose. The addition of cellulose as a natural monomer is to produce a product with superabsorbent properties biodegradable so as not to have a negative impact to the environment. The aim of this research was to determine the potential of rice straw cellulose to be used as a natural monomer in the manufacture of superabsorbent biopolymers. The preparation of this superabsorbent biopolymer was carried out by varying the concentration of the initiator and crosslink agent. Initiator variation potassium persulfate (KPS) namely 0.2 %; 0.4 %; 0.6 %; and 0.8 %; meanwhile, variation crosslink agent in the form of citric acid was 0 g, 2 g, 4 g, 6 g, and 8 g with the addition of 20 g acrylamide. Functional group analysis was carried out by testing Fourier Transform Infrared (FTIR) indicating the presence of -OH, C-H, and C=C functional groups in rice straw cellulose that shows the potential to be the material for producing superabsorbent polymer. The Scanning Electron Microscope (SEM) analysis showed that the morphology of superabsorbent, the surface of the superabsorbent biopolymer looks denser, this indicates that there has been a bond formation between the monomer and crosslink agent. The results showed that the superabsorbent biopolymer produced with variations in initiator concentrations of 0.6 % and crosslink agent 6 g has a water absorption capacity and swelling in solution with buffer acetate the best were 1304.3 % and 10.26 w/w respectively.