Towards Sustainable Agriculture: A CMC‐g‐(ACMO‐SSS) Superabsorbent Resin With High Water Absorbency and Degradation in Soil

ABSTRACT The CMC‐g‐(ACMO‐SSS) superabsorbent resin was successfully synthesized by graft copolymerization of acryloyl morpholine (ACMO) and sodium p ‐styrenesulfonate (SSS) onto carboxymethyl cellulose (CMC), using ammonium persulfate (APS) as the initiator and N , N '‐methylenebisacrylamide (MBA) as the crosslinker. Through systematic optimization via a five‐factor, four‐level orthogonal experimental design, the optimal polymerization conditions were determined comprehensive characterization confirmed the successful synthesis and the resin's excellent properties. FTIR spectroscopy confirmed the successful synthesis. SEM observations demonstrated a highly porous three‐dimensional network structure, which provides abundant space for water absorption. TGA analysis indicated good thermal stability up to 380°C. Gravimetric method yielded a GR of 368.9% and a GE of 48.1% and BET measurement indicated a specific surface area of 1.3702 m 2 /g and an average pore diameter of 5.0227 nm. Relevant test results confirmed the good water absorbency of the resin, reaching 507.95 g/g in distilled water and 82.16 g/g in normal saline. And the resin also exhibited favorable salt resistance, water retention property, and compression resistance. Furthermore, the resin exhibited excellent biodegradability, reaching 39.3% in agricultural soil and 16.5% in desert soil. And the resin still maintained a water absorbency rate of 78% after 5 cycling tests.