Research on synthesis and properties of modified humates-acrylic acid-acrylamide super-absorbent composite

Key words: 
• modified humates /
• acrylic acid /
• acrylamide /
• superabsorbents /
• temperatureresistance and salttolerance

Abstract: The super-absorbent composite was synthesized by aqueous solution polymerization with modified humates, acrylic acid (AA) and acrylamide (AM) as raw material and watersoluble azo as the initiator. The effects of reaction temperature, concentrations of crosslinking agent and initiator, ratio of AA to AM on water absorption were investigated. The optimal condition were as follows: the mass concentrations of cross-linker and initiator compared to the amount of monomer were 0.6% and 0.9%, respectively, reaction temperature was 60℃. Under these conditions, the composite has good properties of temperatureresistance and salttolerance, the absorbencies in distilled water and 0.9% NaCl aqueous solution are 1 298.22 g/g and 261.53 g/g， respectively.