Synthesis of Superabsorbent Resin from Carboxymethyl Cellulose and Acrylic Acid under Microwave Irradiation

The superabsorbent resin was synthesized from carboxymethyl cellulose and acrylic acid under microwave irradiation. The effects of microwave power, reaction time, feeding sequence, mass ratio of raw materials, neutralization degree of acrylic acid, amount of crosslinking agent and initiator were investigated. The optimal synthetic conditions were found as follows: carboxymethyl cellulose (CMC) 2 g, acrylic acid 18 g, deionized water 50 g, NaOH 6.0 g, K2S2O8 0.7 g, N,N′-methylene bisacrylamide solution(1 g/L)4 mL, low microwave power for 2.5 min and vacuum drying temperature 60 ℃. This resin could absorb 738 times of its mass of deionized water. The absorbencies of this superabsorbent resin in tap water, artificial urine, artificial blood and normal saline were examined respectively. The water-absorbing rate, water-keeping capability and regeneration of the resin were also tested.