Synthesis and characterization of hydrogel NaCMC-g-poly(AA-co-AAm) modified by rice husk ash as macronutrient NPK slow-release fertilizer superabsorbent

In this study, sodium carboxymethyl cellulose (NaCMC) based hydrogel grafted by poly (acrylate-acrylamide) by addition of rice husk ash (RHA) and NPK fertilizer to the superabsorbent with in-situ polymerization was successfully synthesized. In this work, the effect of NaCMC concentration and mass of RHA was done. The best water swelling capacity with 3 % NaCMC, 15 % RHA is 480 g/g with percentage of water release capacity is 38 %. Then, the effect of NPK fertilizer concentration on in-situ polymerization was carried out and the best swelling capacity with 5 % NPK mass is 650.10 g/g and percentage of release capacity obtained is 25.20 % for 6 days. The successful of the synthesis of hydrogels NaCMC-g-poly(AA-co-AAm) modified by rice husk ash as macronutrient NPK slow-release fertilizer superabsorbent supported by functional group was characterized by Fourier Transform Infrared (FTIR) and surface morphology by Scanning Electron Microscopy (SEM). The hydrogels based on NaCMC biopolymers and silica from rice husk ash as macronutrient NPK slow-release fertilizer superabsorbent produced slow release can be controlled and a promising material in the future and can be applied in agriculture field.