Synthesis of superabsorbents from Amaranthus starch

A mixture of acrylamide (AM) and acrylic acid (AA) monomers was grafted on gelatinized Amaranthus starch using potassium persulfate (KPS) as an initiator to yield superabsorbent. The effects of different parameters such as time, temperature, monomer feed (AM:AA), starch:monomers ratio and initiator concentration on graft add-on were studied, and the optimized values were found to be 2 h, 65 °C, 1:1 (w/w), 1:1(w/w) and 1% (with respect to starch powder) respectively. The product so formed was saponified with 0.1N NaOH, dried and finely powdered sample was characterized using FTIR, TGA, and XRD. Product showed maximum absorbency of 155 g/g, qualifying itself to be called as superabsorbent.