Bagasse was used as raw material to prepare super absorbent resin with a high water absorption and retention by pretreatment-ultrasonic assisted aquae hydrogenii dioxidi treatment and graft modification. The effects of the ratio of acrylic acid/bagasse, the dosage of initiator, the amount of crosslinker, the neutralization degree on water absorption capacity of resin were studied. IR, XRD and SEM were used to investigate the grafting situation, crystallization, structure and morphology of the bagasse before and after pretreatment and super absorbent resin. The results show that the optimum condition is that the ratio of acrylic acid/bagasse, the dosage of initiator, the amount of crosslinker, and the neutralization degree are 10 mL/g, 0.12 g, 4 mg and 80%, respectively. The pretreatment of bagasse fiber can obviously improve the water absorption of resin. The water absorption capacities of resin in deionized water, running water and 0.9%NaCl solution are 413, 104 and 14 g/g, respectively. The water retention rate of resin reaches 97% by treating the deionized water saturated resin when placed at room temperature for 72 hours.
