A series of superabsorbent polymers (SAP) were synthesized by free radical thermal copolymerization of acrylic acid and N-isopropyl acrylamide monomers using trimethylolpropane triacrylate as crosslinker. They were characterized by FT-IR and thermal stability (TGA/DTG), and evaluated for their water and fertilizer uptake and release characteristics under different crosslinker levels, temperature, pressure, and pH. The observed maximum absorption of water by the SAP was 1130 g/g of polymer. The release was modeled which showed a non-Fickian mechanism. The water uptake of SAP was correlated with the average molecular weight between the crosslinks and crosslink density. Analysis of the weight loss data from TG in air revealed a zero order kinetics for the initial degradation step with an activation energy (AE) of 70.8 kJ/mol. The AEs for water uptake and release for thermal degradation were also determined through Arrhenius plots. The results inferred that the synthesized SAP can be exploited for commercial agricultural applications. (c) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013